Apparatus for selectively rotating a tool relative to the wall of a conduit

ABSTRACT

An improved device (10) is arranged to drill one or more holes through the wall of a subterranean sewer (11). The device includes a frame (13) adapted to be positioned within the sewer and moved to a desired location relative thereto. Three plate-like members (40) are mounted on the frame for movement inwardly and outwardly in a radial direction. An actuator (56) is mounted to the frame, and is selectively operable to move the plate-like members radially outwardly. Each plate-like member carries a motor (18) and a chuck (16) grasping a drill (19). When the motors are energized, the drills rotate. When the actuator is energized, the drills move radially outwardly to bore holes through the conduit wall. The apparatus is used prior to application of grout or sealant in the repair of ground water leaks.

TECHNICAL FIELD

The present invention relates generally to the field of apparatus forselectively rotating a tool relative to the wall of a conduit, and, moreparticularly, to an improved device for selectively drilling one or moreholes through the wall of an underground storm sewer prior to a grout-or sealant-applying operation.

BACKGROUND ART

Sewers are pipes or conduits used to convey or direct various liquids,with or without entrained or suspended solids, from one point toanother. There are generally two types of sewers: sanitary sewers andstorm sewers. Sanitary sewers are used to convey sewage, waste water,and the like from a source (such as a house) to a suitable treatmentfacility. Storm sewers, on the other hand, are generally used to conveydrainage or run-off water. In either case, it is generally desired tominimize the leakage of ground water into the sewer, be it of thesanitary- or storm-type. In the case of sanitary sewers, any such groundwater leakage increases the volume of fluid that must be treated. In thecase of storm sewers, such ground water leakage unnecessarily increasesthe volume of liquid carried by the sewer, and may exceed disposable ordispersal capabilities. Thus, it is generally desired to minimize theamount of ground water entering the sewer.

Sewers develop leaks for various reasons. Whatever the cause, such leakspermit ground water to enter the sewer. The ground water is generallypressurized positively relative to the pressure within the sewer, suchthat the ground water will flow naturally through any leakage path intothe sewer.

The problem of repairing or sealing such leaks in sewers is complicatedby the fact that such sewers are typically subterranean, and may beburied as deep as thirty feet beneath the surface. One technique, ofcourse, is to dig up the entire sewer to expose the damaged portion.Another technique is to apply a grout or sealant from within the sewerto repair the damaged portion. However, such grout or sealant istypically applied to the inside of the sewer. Thus, its integrity isdetermined by the extent to which the grout or sealant adheres to thewall of the sewer. Many sewers are formed of a suitable plasticmaterial, which further complicates the problem of adhering the grout orsealant thereto. Thus, there has long been a need to provide a device toallow the grout or sealant to pass through the sewer so as to bond tothe outside thereof.

Additional details as to prior art sewer repair devices are shown in thefollowing U.S. Pat. Nos. 3,834,422 (Larson), 3,915,197 (Piccirilli),3,951,173 (Larson), 4,170,248 (Bennet et al.), 4,244,895 (Nakashin),4,296,932 (Grobler), 4,529,008 (Appleton), 4,572,228 (Larson et al.),and 4,627,471 (Parkes et al.).

DISCLOSURE OF THE INVENTION

The present invention provides an improved device for selectivelydrilling one or more holes through the wall of a conduit, such as asewer, prior to the application of grout or sealant. By providing suchholes with the improved apparatus, the subsequently-applied grout orsealant may pass through the wall of the conduit and bond to the outsidethereof, so as to provide a long-lasting seal of high integrity.

The improved device broadly includes: a frame adapted to be positionedwithin a conduit and translated (i.e., pulled, pushed, orself-propelled) to a particular desired location therealong; a chuckrotatably mounted on the frame; a motor operatively arranged toselectively rotate the chuck at a desired rotational speed (i.e. eitherfixed or variable); a suitable tool (e.g., a drill) releasably held inthe chuck; and an actuator mechanism acting between the frame and chuckand selectively operable to cause the tool to move away from the frameto engage the wall of the conduit.

Accordingly, the general object of the present invention is to providean improved device for rotating a tool relative to the wall of aconduit.

Another object is to provide an improved device for drilling a plurality(i.e., one or more) holes through the wall of a subterranean sewer,prior to application of grout or sealant.

Still another object is to provide an improved device for enhancing thedurability and life of grout- and sealant-type repairs to subterraneansewers.

These and other objects and advantages will become apparent from theforegoing and ongoing written specification, the drawings, and theappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the improved apparatus, with one of theguides and the various hoses removed for clarity.

FIG. 2 is a fragmentary longitudinal vertical sectional view thereof ofthe improved apparatus in a conduit, and showing the drills as being intheir radially-retracted positions.

FIG. 3 is a fragmentary transverse vertical sectional view thereof,taken generally on line 3--3 of FIG. 2.

FIG. 4 is a further enlarged fragmentary longitudinal vertical sectionalview of a portion of the actuator mechanism, and showing the drills asbeing in their radially-extended positions and as having drilled holesthrough the conduit.

FIG. 5 is a further enlarged fragmentary transverse vertical sectionalview thereof, taken generally on line 5--5 of FIG. 3, and showing thepositions of the radially-retracted drills in solid and the positions ofthe radially-extended drills in phantom.

MODE(S) OF CARRYING OUT THE INVENTION

At the outset, it should be clearly understood that like referencenumerals are intended to identify the same structural elements, portionsor surfaces consistently throughout the several drawing figures, as suchelements, portions or surfaces may be further described or explained bythe entire written specification, of which this detailed description isan integral part. Unless otherwise indicated, the drawings are intendedto be read (e.g., cross-hatching, arrangement of parts, proportion,degree, etc.) together with the specification and are to be considered aportion of the entire "written description" of this invention, asrequired by 35 U.S.C. §112. As used in the following description, theterms "horizontal", "vertical", "left", "right", "up", and "down", aswell as adjectival and adverbial derivatives thereof (e.g.,"horizontally", "rightwardly", "upwardly", etc.), simply refer to theorientation of the illustrated structure as the particular drawingfigure faces the reader. Similarly, the terms "inwardly" and "outwardly"refer to the orientation of a surface relative to its axis ofelongation, or axis of rotation, as appropriate.

Referring now to the drawings, this invention provides improvedapparatus for selectively rotating a suitable tool, such as a drill,relative to the wall of a conduit. As used herein, the word "conduit" isintended to refer generically to many different types of elongatedconduits, tubes and pipes, which are typically used to direct and conveyfluids from one point to another. Such conduits may be cylindrical, ormay have other non-annular cross-sectional shapes as well. Such conduitsmay be formed of steel, plastic, concrete, ceramic or vitrifiedmaterial, or the like. However, the invention is deemed to haveparticular utility in repairing leaks in underground sewer pipes and/ordrains. Thus, while the preferred species will be described withreference to this particular environment, persons skilled in this artwill readily appreciate that the invention is not limited to thisparticular application unless an express limitation to this effectappears in the appended claims.

The preferred form of the improved apparatus, generally indicated at 10,is adapted to be positioned within a conduit 11 and translated to adesired location therealong. The conduit is shown as being asubterranean plastic cylindrical pipe having an inwardly-facingcylindrical surface 12 generated about a horizontal axis x--x.

The improved apparatus broadly includes: an elongated frame 13 having anaxis y--y (FIG. 1) and terminating at an eye 14 at either end; threecircumferentially-spaced longitudinally-extending skids or guides,severally indicated at 15, mounted on the frame and biased to moveradially outwardly therefrom to slidably engage conduit inner surface12; three circumferentially-spaced rotatable chucks, severally indicatedat 16, mounted on the frame for movement inwardly and outwardly in aradial direction; a motor 18 operatively arranged to rotate anassociated chuck at a desired rotational speed (i.e., either fixed orvariable); a suitable tool, such as a drill 19, releasably held in thejaws (not shown) of each chuck; and an actuator mechanism, generallyindicated at 20, mounted on the frame and selectively operable to causethe three chucks to move radially outwardly so as to drill holes in, andpreferably through, the conduit.

As best shown in FIGS. 1 and 2, the frame 13 is a substantially-rigidassembly of a number of component parts, all suitably joined together.More particularly, frame 13 sequentially includes (from left to right):the left eye 14; a left slide block 22; a manifold block 23 providing amanifold for a number of pneumatic connections and terminating in arightwardmost clevis portion 24; a transversely-extendingsubstantially-triangular left vertical plate 25 penetrated centrally bymanifold block 23; three circularly-spaced longitudinally-extendingrods, severally indicated at 26, extending rightwardly from marginalportions of plate 25 proximate the apices thereof: atransversely-extending substantially-triangular intermediate verticalplate 28 suitably secured to the right marginal end portions of rods 26;three circularly-spaced longitudinally-spaced rods, severally indicatedat 29, extending rightwardly from intermediate plate 28 from locationsthereof intermediate rods 26; a transversely-extendingsubstantially-triangular right vertical plate 30 mounted on the rightmarginal end portions of rods 29; and a right slide block 31 extendingaxially rightwardly therefrom and terminating in rightwardmost eye 14.Slide blocks 22 and 31 are severally shown as being provided with threeaxially- and angularly-spaced diametrical through-holes, to accommodatesliding passage of the rods on which the guides 15 are mounted, all fora purpose hereinafter explained. Each of the foregoing frame elements isconnected to its indicated immediate neighbor by suitable means, as morefully shown in the accompanying drawings. Thus, this assembly forms asubstantially rigid frame structure 13 having a longitudinal axis y--y.Rods 26,26,26 and rods 29,29,29 form two axially-spaced cage-likeenclosures for other structure, described infra. The facing surfaces ofintermediate and right triangular plates 28,29 are severally providedwith three aligned pairs of circularly-spaced parallel bosses or lugs,severally indicated at 32, which function to guide radial movement, bothinwardly and outwardly, of the structure on which the chucks and motorsare mounted, as described infra.

Each guide 15 is shown as including a longitudinally-extending skid-likemember 33 provided with an in-turned portion 34 at either end. A nut 35is suitably secured, as by welding or the like, to the inwardly-facingsurface of each skid at each of two axially-spaced locations therealong.Each nut matingly receives the threaded marginal end portion of aradially-extending rod, severally indicated at 36, which is slidablyarranged in one of three diametrical through-holes provided in blocks 22and 31. A coil spring 38 is arranged to act between the associated blockand an annular collar 39 secured fast to each rod between the associatedblock and the skid. Springs 38 are nominally the same, both as to springrate and length, and function to bias the associated skid 33 to moveradially outwardly into continuous engagement with conduit inner surface12. At the same time, these springs, which are located at angles 120°apart, function to urge the two blocks, and hence the frame, to move toa centered concentric position with respect to conduit axis x--x.

Referring now principally to FIG. 4, the three chucks 16 and motors 18are shown as being mounted on three longitudinally-extendingradially-movable plate-like members, severally indicated at 40, therebeing one chuck and motor on each such member. The left and rightmarginal end portions of each plate-like member are slidably received inthe radial slots defined between each pair of spaced parallel bosses32,32. Thus, the three plate-like members, each with its associatedchuck and motor, are mounted for movement in a radial direction atinterval angles of about 120°.

More particularly, each plate-like member is shown as havingradially-extending left and right end faces 41,42, respectively, alongitudinally-extending outwardly-facing surface 42 provided with anintermediate U-shaped recess, and an inwardly-facing longitudinalsurface. This latter surface specifically includes (from left to rightin FIG. 4): an inwardly-facing horizontal surface 43 extendingrightwardly from left end face 41, a leftwardly- and inwardly-facinginclined surface 44, an inwardly-facing horizontal surface 45, arightwardly-facing radial surface 46, an inwardly-facing horizontalsurface 48, another inwardly- and leftwardly-facing inclined surface 49,and an inwardly-facing horizontal surface 50 continuing rightwardlytherefrom to join right end face 42. Inclined surfaces 44 and 49 arearranged in substantially parallel planes. Chucks 16 and motors 18 arearranged in the several U-shaped recesses such that the axes of drills19 are positioned in the radial direction. Each chuck and motor issecured within a recess by means of a manifold block 51, and aselectively-extensible screw-thread connection, generally indicated at52. In other words, connection 52 may be selectively extended to tightlyhold the chuck-motor-manifold assembly within the associated platerecess. Manifold block 42 receives compressed air through a flexiblehose 53 and fitting 54, and contains suitable internal passageways (notshown) communicating with the motor. The three motors may be operatedsimultaneously, or independently of one another, as desired.

As best shown in FIG. 2, two axially-spaced return springs, severallyindicated at 55, are connected to the outer marginal end portions ofadjacent plate-like members. These springs are in tension, andcontinuously urge the three plates to move radially inwardly towardtheir retracted positions (FIG. 2).

Still referring principally to FIG. 2, actuator mechanism 20 broadlyincludes a fluid-powered actuator 56, and an actuator rod 58 operatedthereby. Actuator 56 has a cylinder portion 59 and a rod portion 60. Thecylinder portion has a left eye 61 received and held in the frame clevis24 by means of a transverse retaining pin. The rod portion 60 has aclevis 62 at its right end, which receives an eye 63 mounted on the leftend of rod 58. The overall length of rod 58 is variable by means of ascrew-thread connection, generally indicated at 64. A coil spring 65encircles rod 58 and is arranged to act between frame plate 28 and therod, and continuously urges the rod to move leftwardly toward itsaxially-retracted position relative to the cylinder. Of course, if adouble-acting actuator is used, spring 65 may be eliminated altogether.In any event, rod 58 carries two axially-spaced cam members. These cammembers include frusto-conical cam surfaces 66 arranged to normallyslidably engage plate surfaces 44,49, and have a short outwardly-facinghorizontal cylindrical surfaces 68 arranged to engage plate innersurfaces 45,50, when the plate is in its radial outwardmost position (asshown in FIG. 4).

The various motors and actuators are preferably fluid-operated. Thesemay be conveniently powered by compressed air supplied by a suitablesource (i.e., an air compressor) on the surface. Such compressed air maybe fed down to the device by means of flexible conduits and/or hoses,which have been eliminated from the accompanying drawings in theinterest of clarity. In the preferred embodiment, one valve is used tocontrol the flow on compressed air to all three motors 18. However, asindicated above, these motors could, alternatively, be controlledindependently of one another. Another flexible conduit (not shown) isarranged to supply compressed air to actuator 56, to selectively movethe chucks and drills radially outwardly. When such fluid in the chamberof actuator 56 is vented, return spring 65 urges rod portion 60 toretract axially within cylinder portion 59, and return springs 55 urgethe three plate-like members to move radially inwardly of the frame.

Thus, the improved apparatus is adapted to be positioned within aconduit, and translated to a particular location therealong. Thespecific means for translation (not shown) may simply include anappropriate rope or cable (not shown) connected to left and/or righteyes 14, and used to selectively pull the improved device to suchdesired location. Various ancillary means and mechanisms may be used toaid in the positioning of the improved device within the conduit. Forexample, the position of the improved apparatus relative to the conduitmay be determined by means of closed-circuit television monitors. Theseare normally used in the subsequent grouting operation, and, hence, maybe readily available on site. Once in position, compressed air issupplied to the device to cause motors 18 to rotate. This causes thethree chucks and drills to rotate about their respective axes.Thereafter, compressed air may be supplied to actuator 56 to cause thethree plate-like members to move radially outwardly such that the drillswill bore holes through the conduit wall. Once this has been done, theair in actuator 56 is appropriately vented, and the return springs 55radially retract the three plate-like members, together with the drillsand motors carried thereby. Thereafter, the apparatus may be movedfurther along the conduit, or withdrawn, as desired.

After the holes have been drilled in the sewer, the conventionalgrouting apparatus may be used to apply grout and/or sealant thereto.However, with such deliberately-provided holes of relatively-largediameter when compared to cracks, the grout may more freely pass throughsuch holes and bond to the outside of the sewer, thereby providingsubstantially enhanced life and integrity to the seal.

Of course, persons skilled in this art will readily appreciate thatvarious changes and modifications may be made. For example, rather thanbeing pulled along the conduit, the apparatus could be made to beself-propelled. The various motors and actuators may be pneumatically-,hydraulically-, or electrically-operated, as desired. If a double-actingactuator is used, return spring 65 may be eliminated. Other means may beused for biasing the three plate-like members to move toward theirradially-retracted positions. Moreover, the invention is not limited touse with three plate-like members, each carrying its own motor and/ordrill. Any greater or lesser number may be used, and these may bepowered by the same source, or may be powered by independent sources.Similarly, while it is presently preferred to use the improved apparatusto drill holes through a subterranean sewer, persons skilled in this artwill readily appreciate that other types of rotatable tools could besubstituted therefor and used to perform other operations as well. Itshould also be apparent that other types of skids or centering devicescould be substituted for those shown.

Therefore, while the preferred embodiment of the improved device hasbeen shown and described, and several modifications thereof discussed,persons skilled in this art will readily appreciate that variousadditional changes and modifications may be made without departing fromthe spirit of the invention, as defined and differentiated by thefollowing claims.

We claim:
 1. Apparatus for selectively rotating a tool relative to the wall of a conduit, comprising:a frame adapted to be positioned within said conduit and translated to a desired location therealong; a chuck rotatably mounted on said frame; a motor operatively arranged to selectively rotate said chuck at a desired rotational speed; a tool releasably held in said chuck; and an actuator mechanism acting between said frame and chuck and selectively operable to cause said tool to move away from said frame to engage said conduit wall, said actuator mechanism including a plate mounted on said frame for movement in a substantially radial direction relative to said conduit wall, wherein said chuck and motor are mounted on said plate, wherein said plate is provided with an inclined surface, and further comprising a member having a cam surface engaging said plate surface, and an actuator acting between said frame and cam member for selectively causing said surfaces to move relative to one another.
 2. The apparatus as set forth in claim 1 wherein said frame is adapted to be pulled along said conduit to said desired location.
 3. The apparatus as set forth in claim 1, and further comprising:a plurality of guides mounted on said frame and engaging said conduit wall to maintain said frame in a substantially centered position relative to said conduit.
 4. The apparatus as set forth in claim 3 wherein three of said guides are provided, and wherein each guide includes a skid biased to move outwardly from said frame.
 5. The apparatus as set forth in claim 1 wherein said motor is a pneumatic motor.
 6. The apparatus as set forth in claim 1 wherein said tool is a drill.
 7. The apparatus as set forth in claim 1 and further comprising a return spring acting between said frame and plate for holding said surfaces in contact with one another. 